In the case of navigation systems in vehicles or for use in connection with vehicles, it is conventional to represent the present geoposition in the surround field of a geographical map. For example, in a navigation system, the scale selected for the representation of the geographical map may be a function of the speed driven, the type of road traveled, or a selection by the user.
German Published Patent Application No. 197 33 650 described representing both a general map and a detail map in a display apparatus for a navigation system.